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Finding the Fourth Proportional to 305.04, 421.04 and 206.90

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Solution

The fourth proportional to 305.04, 421.04 and 206.90 is: 285.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    305.04 : 421.04 = 206.90 : x
  2. Step 2: Convert to fraction form
    305.04/421.04 = 206.90/x
  3. Step 3: Cross multiply
    305.04x = 421.04 × 206.90
  4. Step 4: Simplify right side
    305.04x = 87,113.18
  5. Step 5: Solve for x
    x = 87,113.18/305.04
  6. Step 6: Final answer
    x = 285.58

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.